1. Field of the Invention
The present invention relates to a water filtration media having a charged material affixed directly to binder material used in the fabrication of the filter media. A microbiological interception enhancing agent may also be added to the binder directly. In one embodiment, the present invention relates to a method of making a filter media having a charged material and a microbiological interception enhancing agent both affixed directly on a binder material. The resultant enriched binder is then combined with core filter media and prepared as a filtration media.
2. Description of Related Art
Generally, carbon or activated carbon fibers or structures that form the core filter media in a filtration system may be chemically treated with charged material and/or any compatible microbiological interception enhancing agent, with or without a biologically active metal. A binder or thermoplastic material in powder, particulate, or fiber form, is then combined to provide enhanced strength. In some instances, the activated carbon/binder combination is chemically treated with charged material and compatible microbiological interception enhancing agents.
The prior art does not teach combining charged material directly to the binder, or combining a microbiological interception capability directly to the binder, with or without the addition of charged material.
Microbiological interception enhancing agents that comprise a cationic silver complex are known in the art. Generally these agents are deposited on either carbon block or fiber filters for water purification and demonstrate excellent viral and bacterial interception. The method for depositing the agent in these applications has been known to be rather complicated. A cationic silver complex (charged material) is generally formed directly on activated carbon in a two step treatment process. The activated carbon is treated by cationic material and then reacted with silver ammonia complex to form a cationic silver-amine-halide complex. This process has been taught in part by the following U.S. Pat. Nos. 6,630,016; 6,835,311; 6,953,604; 6,959,820; 6,998,058; 7,008,537; 7,011,753; and 7,144,533, which were issued to Koslow, and assigned to KX Technologies LLC.
A silver ammonia complex is prepared by reacting a silver nitrate solution with sodium chloride to precipitate silver chloride. The silver chloride is washed thoroughly to remove completely nitrate ions. The concentration of nitrate ions is monitored during the rinse. A large amount of ammonia solution is then used to dissolve the silver chloride to form a silver ammonia complex solution. The activated carbon is then treated and dried at approximately 300° F. for a period of time, typically overnight.
The present invention deviates from this known process insomuch as the charged material or the microbiological interception enhancing agents, or both, are added directly to the binder material that provides the structural integrity for the activated carbon.